Brown-colored insecticide for use on tobacco plants



- Patented Apr.- 13.1 926.

' more particularly to a. brown colored inleadis used on tobacco plantsit'produces on tion of.-'an insecticide which itself possesses thedesired color and more specifically to trimanganoarsenate for follows:

and useful Improvements in Brown-Colored which the following is aspecification.

I plant products by theinsecticide. -For in is found however thatorganic dyes are not sutliciently permanent and that the use of 1colored pigments is not satisfactory because i a comparatively largequantity is required 30.

[alents ofa 'solution of arsenic acid is a ded.

formation of a jelly like "precipitate of a @white to light pink color.-*In order tools:

the: amount of water employed 'in the rer 1,580,260 UNITEDTS'TATESPATENT OFFICE.

HENRY HOWARD, O CLEVELAND, OHIO, assmuon r0 THE GRASSELLI cnnmrcancomrnny, or CLEVELAND, 01110, A conrona'rron or OHIO.

' nnown-cononnn msncrrcrnn r03. USE on monacco PLANTS.

1T0 Drawing. AppHcation nled May 15,1922. 'Serial No. 561,012.

To azlwhom it ay concemr gelatinous mass containing the acid salt of Beit known that I, HENRY HOWARD, a manganese with arsenic acid and oneequiviti of th i -Unit d States, residing at alent of unchangedmanganese carbonate. Cle la d, i the county of Cuyahoga and Thismaterial ma} be'converted to the neu- State of Ohio,fihave inventedcertain new 'tral salt, trimanganoarsenate by boiling with water but Iprefer to form the neutral salt by dry heating.

- The bulky material is first dried in a steam dryer and is then heatedin a niuflle furnace for from two to three hours at from 500 to 600 C."It is then pulverized, preferably in a ball mill, and if a. product ofless den-- s1ty is. desired the pulverized material may be subjected toareation to separate the light trom the-heavy particles.

I The product formed as described contains fLS'percent or more of AS 0It is brown incolor suspensible'inwater and insoluble. the dried andcured leaves an appearance It may be employed as an insecticide eitherInsecticide for Use on Tobacco Plants, of

This invention relates to colored insecticides suitable for use oncertain plants and secticide for use on tobacco plants.

Considerable difficulty has been' expe-' rienced in the-use ofinsecticides due to undesirable coloration 0r discoloration of thestance, when the usual white arsenate of of mould which reduces theselling price of in the dry form or in the form of a sprayv whensuspended in water. In order to imthe tobacco. There is therefore ademand prove its suspensible properties a small for an insecticide whichwill not produce undesirable coloration of the plant products.

Efforts have been made to. color insectisuitable suspension promotin aent ma be cides such as the whitearsenate of lead. It g a y added. Onaccount of its relatively high brown colored pigment such as amber inproportion up to one part of American burnt umber to two parts of thearsenate. In this way the color of the product may be modified,- theprice per und reduced, and a product ofsubstantially the same arseniccontent as commercial lead arsenate, that 1s, about 34 percent As Oproduced.

The'reactions involved in thepreparation of trlma-nganoarsenate areunderstood'to be plg'iltl's l h d f th. (1 t as follows:

economica met 0 or e r0 110 ion of such an insecticide in finelydiiiided form V M 8+ 8 4 and capable of" suspension in water is as to bemixed with the insecticide and the arsenic content of the product is toolow.

Thisinvention is directed to the producthe production'of an insecticidecontaininguse on tobacco 9 Three molecular equivalents of manganese2MnHASO+MnCOs+heat carbonate are stirred into, water heated to from toG.,'and two molecular e uiv- :process is conveniently prepared bprecipitation from a solution of a solub e manganese salt such as thesulfate or chlorid by means of soda ash (sodium carbonate). Theprecipitate is filtered and washed and An energetic reaction takes placewith the tainas complete precipitation as is possible action mixture isrestricted to a quantity scribed-above.

i justsufiicient to permit free stirring or agitation. The precipitate;is. thenseparated 11 claim: I 1. A brown colored from the reaction,mixture by draining or dividedjorm capable of suspension in'waterfiltering. The separated precipitate 1s a comprising trimanganoarsenate.

the wet cake is stirred into water as deamount (about 1 percent) ofgoulac or other arsenic content it may be mixed with a insecticide infinely v ganese and a brown colored inert material.

4. An insecticide comprising a finely di vided mixture oftrimanganoarsenate and umber. V

5. An insecticide comprising a mixture of trimanganoarsenate and a browncolored inert material, said mixture containing not less than 34 percentof AS205.

6. An insecticide comprising about two parts of a brown colored productcontaining an arsenate of manganese and having an arsenic content ofnot. less than 48 percent of AS 0 and about-onepart of burnt umber. r

7 Process of making a brown colored msecticide' which comprises reactingupon manganese carbonate with arsenic acid, pulverizinothe resultingmaterial and mixing the pn verized product with burnt umber. 1

8. An insecticide comprising trimanganoarsenate. p

In testimony whereof, I affix my signatin-e.

HENRY HOWARD.

